1. Field of the Invention
The present invention relates generally to catamenial devices or tampons. More particularly, the present invention relates to catamenial devices or tampons adapted to provide a signal to the user. The present invention further relates to catamenial devices or tampons that signal the user upon exhaustion of the absorbent pledget, while providing a leakage protection benefit.
Women have to use a destructive test to ascertain whether a tampon has remaining absorbent capacity. Specifically, the tampon must be removed to determine whether it has been used to capacity. Even if not completely full, the tampon usually is not reinserted. Generally, a woman removes a tampon before it has reached its capacity in order to prevent an accident. Namely, if the capacity is exceeded, the excess menses flows, unimpeded from the vagina, to soil the user""s clothing.
Presently, one criterion used for determining when to remove a tampon is elapsed time since insertion. The elapsed time criterion is not satisfactory for several reasons. The menstrual flow rate varies throughout the menstrual period. Thus, much of the absorbent capacity of a tampon is wasted due to the tendency to change the tampon to avoid accidental leakage. The flow variations throughout the menstrual period cause problems as to how long to use or wear a tampon since a woman cannot establish a definite time period in which the absorbent capacity of a tampon is sufficient. Additionally, a phenomenon, in which menses leaks before the tampon nears its full potential absorbency, occasionally occurs. This is generally known as by-pass leakage. This leakage is usually not predictable by the user""s habitual wearing time. Therefore, a woman is in a quandary as to how long to wear the tampon during the varying menstrual flow days.
Larger and more absorbent tampons permit a woman to change tampons less often. However, larger tampons do not approach the goal of fully exhausting the absorbent capacity of the tampon, nor preventing accidents due to by-pass leakage.
2. Description of the Prior Art
Attempts have been made to provide a signal to a user when a sensory indicator is contacted by a body fluid. For example, U.S. Pat. Nos. 5,649,914, 5,702,376, and 5,797,892 issued to Glaug et al., on Jul. 22, 1997, Dec. 30, 1997, and Aug. 25, 1998, respectively, describe a toilet training aid. The aid is in the form of a pad that creates a temperature change sensation, a wet sensation, a dimensional change sensation, or a combination thereof when contacted by urine. Another example of a toilet training aid pad with a temperature change sensation signal is described in U.S. Pat. No. 5,681,298, to Brunner et al., that issued on Oct. 28, 1997.
There have been attempts to detect menstrual fluids. For example, U.S. Pat. No. 5,647,863, to Hammons et al., that issued on Jul. 15, 1997, describes a sanitary napkin. The napkin provides a signal by way of an indicator member that becomes noticeably stained when the storage capacity of the sanitary napkin is substantially exhausted. U.S. Pat. No. 5,728,125, to Salinas, that issued on Mar. 17, 1998, describes a sanitary napkin having a temperature-sensitive reactive chemical product that can respond by turning cold when it contacts and dissolves in a menstrual flow.
What is lacking and needed in the art is a tampon that provides the user with a signal when the tampon has reached its maximum absorbent capacity, or is about to leak, i.e. by-pass leakage, even though the tampon is not full.
It is an object of the present invention to provide a tampon that can be worn until essentially all of the absorbent capacity is exhausted.
It is also an object of the present invention to provide such a tampon that alerts the user when essentially all of the tampon""s absorbent capacity is exhausted.
It is another object of the invention to provide such a tampon that alerts the user that by-pass leakage is about to occur.
It is also another object of the present invention to provide such a tampon that has a sensual, absorbent capacity signal associated therewith.
It is a further object of the present invention to provide such a tampon having additional leakage protection.
Accordingly, there is provided a tampon that comprises an absorbent pledget and a menstrual fluid indicator associated therewith. The absorbent pledget has a proximal end that is placed near the cervical bone and a distal end opposite the proximal end. The indicator is preferably an additional layer formed and in contact with the entire circumference of the absorbent pledget and is located near the distal end. The indicator is designed to provide a sensory signal to the user when the capacity of the absorbent pledget of the tampon is exhausted, or when by-pass leakage may occur.